R & D

Reamed and Drifted. Pipe commonly used in water wells having a special, heavy-duty coupling and a guaranteed I.D. clearance.

RF

Recovery Factor - Rating based on the efficiency of the product which is input required to raise 1 gallon of water 1 degree Fahrenheit.

Rail Fittings

Fittings with setscrews rather than threads, which hold pipes used for hand railings. Available in various sizes and configurations to suit a number of applications. Not used for plumbing or conduit.

Rated Storage

Volume Quantity of water stored in a tank.

Raw Water

Water supplied to the plant before any treatment.

Reamer

A grinding tool used to level or remove burrs from valve seats in faucets so that the valve stem will fit properly.

Recessed Tub

A tub that has a decorative finish on one side only, and surrounded by three walls. The apron, or skirting, may not be included and must be ordered separately. The most popular style.

Recirculating Harness

PVC tubing setup that circulates water throughout a whirlpool system, delivering water to the jets.

Recovery

The amount of water in gallons that can be heated in one hour. (gph).

Recovery Capacity

The amount of water in gallons per hour raised 100 degrees F at a given thermal efficiency and BTU per hour input.

Red Water

Water which has a reddish or brownish appearance due to the presence of precipitated iron and/or iron bacteria.

Reducer

A fitting that connects pipes of different sizes together.

Reed Switch

A serviceable, magnetic sensing switch that triggers the water flow to stop when the neck jet pillow (with magnet) is removed from the whirlpool.

Refill Tube

The tube that directs water from a ballcock into the overflow tube to refill the bowl after a siphon break.

Relief Valve

A valve that opens to relieve excess temperature.

Repair Clamp

Sleeve type clamp used to repair a split pipe, held in place by bolts.

Return Circulation System

Tempered water from or near the point of usage which eliminates waste of hot water used for long runs and adds storage to the system.

Revent

Pipe installed specifically to vent a fixture trap. Connects with the vent system above the fixture.

Reverse Osmosis

A water treatment method whereby water is forced through a semi permeable membrane which filters out impurities.

Reverse Trap Water Closet

A water closet having a siphonic trapway at the rear of the bowl, and integral flushing rim and jet. Min. dimensions are 9" x 8" water spot and 1 ½" ball pass.

Rigid Pipe

Pipe designed to transmit the backfill load to the foundation beneath the pipe. Rigid pipe must be supported on the bottom portion of the pipe

Rim Holes

A series of small holes in the underside of a toilet rim, around the circumference of the bowl. Incoming water flows down into the bowl through these holes, creating a rinse effect or wash over the entire inner surface of the bowl.

Riser

A vertical metal or plastic tube or assembly that connects a faucet to the water supply stop valve. Usually made of copper. Metal Flex Risers are corrugated to facilitate bending. Also a supply line that rises from one story to the next.

Residual Chlorine

Chlorine Chlorine remaining in treated water after a specified period of contact time to provide continuing protection throughout a distribution system; the difference between the total chlorine added, and that consumed by oxidizable matter.

Roller Hanger

A pipe hanger similar to a clevis hanger except that the yoke bolts to a roller rod instead of a metal strap. This roller rod supports the pipe and permits horizontal movement.

Roman Spout

Deck-mounted faucet spout.

Roof Drain

A drain installed at the low spot in a roof that channels water into a drainpipe to prevent pooling.

Roof Flashing

Sheet metal installed at any break in a shingled roofline to prevent leaks. Also around sewer vents, fluepipes.

Root Valve

A multi-port valve commonly used on gauges or switches in high pressure, high temperature, or under otherwise severe process conditions. Typically built with non-rotating and non-threaded stems.

Rough-In

Installation of the drain, waste, vent, and supply lines in a structure to the proposed location of each fixture.

Rough-In Dimensions

The distance from a finished wall or floor to the center of the waste or supply opening or mounting holes on a plumbing fixture.

Round Front Bowl

Standard shape of the front of a toilet bow, having dimensions of 14" wide by 16 ½" long from center of seat hinge holes to front outside rim edge.

Run

A complete or secondary section of pipe that extends from supply to fixture or drain to stack.

Running Trap

An in-line trap mounted in a horizontal drainpipe, where the inlet and outlet are parallel.